Elimination of Flammable Gas Effects in Cerium Oxide Semiconductor-Type Resistive Oxygen Sensors for Monitoring Low Oxygen Concentrations

We have investigated the catalytic layer in zirconium-doped cerium oxide, Ce0.9Zr0.1O2 (CeZr10) resistive oxygen sensors for reducing the effects of flammable gases, namely hydrogen and carbon monoxide. When the concentration of flammable gases is comparable to that of oxygen, the resistance of CeZr...

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Bibliographic Details
Main Authors: Toshio Itoh, Noriya Izu, Takafumi Akamatsu, Woosuck Shin, Yusuke Miki, Yasuo Hirose
Format: Article
Language:English
Published: MDPI AG 2015-04-01
Series:Sensors
Subjects:
Online Access:http://www.mdpi.com/1424-8220/15/4/9427
Description
Summary:We have investigated the catalytic layer in zirconium-doped cerium oxide, Ce0.9Zr0.1O2 (CeZr10) resistive oxygen sensors for reducing the effects of flammable gases, namely hydrogen and carbon monoxide. When the concentration of flammable gases is comparable to that of oxygen, the resistance of CeZr10 is affected by the presence of these gases. We have developed layered thick films, which consist of an oxygen sensor layer (CeZr10), an insulation layer (Al2O3), and a catalytic layer consisting of CeZr10 with 3 wt% added platinum, which was prepared via the screen printing method. The Pt-CeZr10 catalytic layer was found to prevent the detrimental effects of the flammable gases on the resistance of the sensor layer. This effect is due to the catalytic layer promoting the oxidation of hydrogen and carbon monoxide through the consumption of ambient O2 and/or the lattice oxygen atoms of the Pt-CeZr10 catalytic layer.
ISSN:1424-8220